Case Study 8 



Galaxy Formation 



Visualization of a small portion of the computational results of an astropfiysical simulation of 8. 8 million 

 gravitating bodies run on 512 nodes of tf)e Concurrent Supercomputing Consortium's Intel Toucfistone 

 Delta System. The image shows about 137,000 gravitating bodies that form a single halo about 400 mega- 

 parsecs across. Color represents projected density along the line of sight, i.e.. different colors correspond 

 to pixels that "contain" different numbers of bodies. Densities are much higher at the center of the object. 

 The entire simulation contained about 700 halos like the one depicted here. 



The process by which galaxies form is among 

 the most important unsolved problems in 

 physics. There is a wealth of observational data 



- modem observations span the electromagnetic 

 spectrum from radio frequency to gamma rays. 

 However, a firm theoretical understanding is yet 



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